Move the signal lever down (for a left turn) or up (for a right turn) to the stop position. The signal will self-cancel after the turn is completed.
If the indicator light continues to flash after a turn, manually return the lever to its original position.

The turn signal indicators in the instrument cluster flash according to the operation of the turn signal lever to show which signal is working.

NOTE
Turn and Lane-Change Signals
Lane-Change Signals and Three-Flash Turn SignalMazda 6 Owners Manual: Dtc c1955, c1956
Caution
When attaching the tester lead to the DSC HU/CM connector the SST
(49 G066 004) must be used.
Diagnostic procedure
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Mazda 6 Owners Manual: Intake air temperature (iat) sensor inspection
Resistance Inspection
Note
Perform the following inspection only when directed.
1. Disconnect MAF/IAT sensor.
2. Measure the resistance between the MAF/IAT sensor terminals D and E using
an ohmmeter.
If not as specified, replace the MAF/IAT sensor.
If the MAF/IAT sensor is okay, but ...